The grieving grandmother of two young children who were slaughtered in the bathtub of their luxury Manhattan apartment today revealed how the family is struggling to make sense of the killings.

'It's just a horror story,' Karen Krim told RadarOnlineon Wednesday from her Camarillo, California, home. 'I was their grandmother. It is really horrible.'

Police believe Lucia Krim, aged six,
and her two-year-old brother, Leo, were killed by their nanny, Yoselyn
Ortega, who then attempted to take her own life by slitting her wrists and throat.

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Charged: Nanny Yoselyn Ortega, pictured with Lulu Krim, right, and Nessie, left (who was not in the apartment during the attack), has been charged in their murder

Discovery: Marina Krim holds onto her daughter, three-year-old Nessie, after finding her two other children, two-year-old Leo and six-year-old Lulu, stabbed to death allegedly by their nanny

The childrens' mother, Marina Krim,
returned home October 25 with her youngest daughter to find her Lucia
and Leo dead in a pool of blood before walking in on Ortega stabbing
herself in the throat.

In a brief interview this week, Karen
Krim, the slain children's paternal grandmother, said that they
continue to grapple with the horrific crime.

'Under the circumstances, we are all doing as well as can be expected,' she said.

Karen Krim's comments come just days
after Ortega was brought out of medically-induced coma and charged with
first-degree murder.

When
questioned by police for the first time Saturday, the nanny attempted
to paint Marina Krim in a bad light, shifting part of the blame for the
tragedy on her.

Ortega revealed from her hospital bed
that she resented her employers because they kept telling her what to
do and asked her to do the housework. She also said she was involved in a vicious argument with the children's mother one day before the brutal homicides.

Ortega waived her right to have a lawyer present during questioning when she ominously told the detective, 'Marina knows what happened', a source told theNew York Times.

Meanwhile, somber, black-clad family
and friends gathered on Monday in Manhattan's Avery Hall to pay tribute
to little Lucia and Leo.

Breaking down in tears, father Kevin
Krim recalled the happy days he and his wife Marina shared with their
children in their Upper West Side apartment, and asked that the lives of
their 'best friends' be celebrated rather than mourned.

Krim, his wife and their surviving daughter, Nessie, have been in seclusion since the murders.

Over the weekend, RadarOnline reported that Ortega 'told NYPD detectives that she was involved in an epic argument
with Marina Krim the day before the children were tragically murdered.'

Father: Kevin Krim recounted the magical Manhattan childhood of his two lost children, the happy memories they accumulated before, police said, their trusted nanny murdered them

Service: Family music teacher Daniel Bogart, performs Daughter by Loudon Wainwright III and closed with the Jack Johnson song Go On

Stage at Avery Fisher Hall, Lincoln Center: Heartbroken parents, Marina and Kevin Krim said they wanted to 'celebrate the beautiful lives of Lulu and Leo', not remember them as victims

'Yoselyn also said that when she left at the end of the day before the murders, Marina ignored her when she said good-bye and this made her very, very angry,' Radar's source continued.

Yoselyn became extremely animated when she discussed the incident with police, telling officers that she had numerous disagreements with mother
Marina about how the kids were being cared for.

Marina didn't think
Yoselyn was interacting with the kids enough and was giving them junk
food when she was out of sight.

Ortega told police when she woke up
from her coma that she was angry because the family wanted her to clean
as well as look after the children.

While being interrogated Yoselyn repeatedly asked about her family
and asked how they were doing.

She didn't express remorse or cry when talking about Lucia and Leo's murders.

'It was rather shocking
to cops because of the gruesome crime scene that Yoselyn didn't express
any emotion when speaking of the kids. Everything was just rather
matter of fact,' Radar's source reported.

Yoselyn was not on medication Saturday and still seemed 'spacy' during the hospital room chat.

A Dominican Republic native, Ortega was questioned by police after allegedly butchered six-year-old
Lucia and two-year-old Leo while they were under her care at an Upper
West Side, Manhattan, apartment last week.

Law
enforcement officials told the New York Post that Mr and Mrs Krim asked
their financially-strapped nanny to do simple housework as a way to
earn money, thinking they were doing her a good turn. All this did was
enrage her.

'She said something like, "I'm paid to watch the children, not clean up and do housework",' a law-enforcement source said of Yoselyn Ortega’s statements to police after she woke up from a medically-induced coma on Sunday.

'There was friction between her and the family.'

In Ortega's brief statement to police, she said her employers had arranged to give her an extra five hours a week in housekeeping work to help her make more money, law-enforcement sources told the Post.

'They were asking her to clean and do housework and she was unhappy because it interfered with her doctor's appointments.'

It was also revealed today that Marina and Kevin Krim were worried about Ortega's job performance in the weeks leading up to the October 25 slaying and had told her that if she didn't improve her job performance they might need to replace her.

A law-enforcement source told the Post: 'She was told that if she didn't improve her work, she would be let go.'

Last week, the mother of CNBC executive Kevin Krim said that the young family treated Ortega, as they would one of their own, 'bending over backwards' to help her and even buying plane tickets so she could fly to the Dominican Republic with them.

Loss: Lulu and Leo, pictured, each had multiple stab wounds and were pronounced dead in hospital

Tragedy: Six-year-old Lulu, top, and her baby brother Leo, right, were found dead in the bathtub after they had been stabbed by their nanny. They are pictured with sister Nessie, 3, who was not hurt

Happier times: Marina and Kevin Krim, pictured at a 2009 event at Tavern on the Green in Central Park

Oretega allegedly repaid this kindness
by murdering her children before trying to kill herself. Marina Krim
discovered her son and daughter, Leo and Lulu, in a pool of blood in a
bathtub, each with multiple stab wounds.

She was due to meet Ortega and her
other two children at the local swimming pool with her now only
surviving child Nessie, three. But when they failed to show up, she
returned to her three-bedroom, $10,000-a-month pre-war apartment at West
75th Street and found it dark, Police Commissioner Ray Kelly said.

When she went into the bedroom, she discovered her children in a pool of blood and a bleeding Ortega.

The nanny, who had slit her wrists,
then plunged a kitchen knife into her own neck as the horrified mother
walked into the grisly scene, police said. She stabbed herself with such
force that she fractured a vertebra in her neck, police said.

Though she looked after the children
for two years and was treated like part of the family, the 50-year-old
did not ask about them when she woke from her coma, asking instead about
her own family before falling back under sedation. Police plan on
questioning her again. Charges have yet to be filed.

Ortega's sister Miladys said she spoke
to her sister in the days leading up to the massacre and she gave her
no indication anything was wrong.

But the nanny's neighbors said she
appeared in troubled in the weeks leading up to the murders and she had
been struggling with money issues - which is why the Krims offered her
more work.

Scene: Crime scene unit officials enter the luxury apartment building where the stabbings took place

Ortega remains at nearby New
York-Presbyterian/Weill Cornell Medical Center. Toxicology tests
performed on Ortega came back negative.

Neighbor Rima Starr, 63, recalls the
moment she heard Mrs Krim make the grisly discovery.: 'I heard blood
curdling screams and I went down to the lobby and there was the mother
screaming, hunched over the three year old.

'At time she was screaming things
like: "I'll never speak to her again", repeating that over and over
again, then "it's all right, you'll be all right, you'll be alright" to
the child.

'Then she would get waves of the
reality of what just happened and then she'd go into just plain
bloodcurdling screams with her arms flailing out to the sides.'

One neighbor revealed the
superintendent of the apartment block went into the apartment and
questioned Ortega, demanding: 'So you cut her throat? So you stabbed her
in the neck?'

His wife then came
out to assist and told horrified neighbours who had heard the screams:
'Two babies, in the bath, nanny' and made a cutting sign across her
throat.

Mrs Friedman added: 'At that point I knew the nanny had something to do with it'.

Neighbours dialed 911 and, although Lulu and Leo reportedly appeared to be breathing when medics arrived, they were pronounced dead on arrival at hospital.

Ortega was unresponsive but was taken to New York-Cornell Hospital in a critical but stable condition. She was in a stable condition on Friday morning and police sources say she may have also taken pills.

Scene: The murders occurred at La Rochelle, a luxury prewar building on Manhattan's Upper West Side

Paying respects: A woman leaves flowers in front of the building

Mrs Krim and Nessie, who had not witnessed the grisly scene, were also taken to hospital for treatment, and Mrs Krim was sedated.

A neighbour told the Wall Street Journal the woman had left the building 'inconsolable, hysterical, frantic'.

Her
husband, Kevin Krim, had been on a business trip and was met by police
at the airport when he returned to New York. Officers recounted the
horror to him and he was escorted to the hospital.

Mr
and Mrs Krim remained at St. Luke's hospital last night with Mrs Krim's
sister. Police said the shocked mother was unable to communicate.

On Friday,
neighbour Charlotte Friedman said she believes she was the last one to
see the children alive and that the nanny had looked 'cold' just half an
hour before the murders.

She
said that she was in the elevator with Ortega, who had a 'poker face'
and appeared unemotional despite Lulu and Leo playing around.

Distress: On Friday morning, a woman and two children visit the apartment where the youngsters were killed

Sadness: A mourner places flowers outside the apartment as she breaks down in tears

Struggled: A woman cries at a memorial outside the apartment building just a block from Central Park

Sympathy: A touching note left outside the apartment block on West 75th Street on Friday afternoon

'I was playing with the children in the
elevator,' Friedman said. 'The girl looked so delightful. I asked her if
she was going on a play date or something and she said she was going
home.

'I said, "What did you do," and she said, "Dancing." And that was it - they were only on the second floor so they left.

'She was smiling, happy, happy happy. The nanny just smiled - and nothing. The nanny was a colder type from most nannies that I have encountered.

'She was poker faced. She wasn't the warmest person. I never saw her as the warmest nanny.'

Ortega's niece,
Katherine Garcia, added that her aunt had been 'acting kind of nervous
lately' but insisted that she had loved the children.

Friends said she had lost her apartment in the Bronx and was forced to move in her sister in Harlem. Police added that her family said she may have visited a psychologist recently.

Police said there
were no immediate explanations for the murders and suicide attempt. Paul
J. Browne, from the police department, told the New York Times he did
not know a note had been left.

Family: Lulu is pictured with her father Kevin Krim and mother Marina Krim, who found her children stabbed in the bathtub and their nanny with a slit throat and wrists on the bathroom floor

Horror: Marina Krim's screams could be heard through the building after she found her stabbed children, right

Heartbroken: Marina Krim, pictured with Leo, was taken to hospital and had to be sedated

The family had moved to New York from San Francisco within the last few years, and Mr Krim was named general manager of CNBC's digital media division in
March.

He is a Harvard graduate and has recently worked at Bloomberg and Yahoo, according to his LinkedIn profile.

The children's
grandmother on their father's side, Karen Krim, told said that the
family hired Ortega a year ago, until which time Mrs Krim had been a
stay-at-home mother.

When
Leo was born, they searched for a nanny. They even spent nine days with
her family in the Dominican Republic, as documented on Mrs Krim's
online journal.

'They just bent over backwards being nice to this woman,' Karen Kim told the New York Daily News.'They were always doing things that were just fabulous for her. I’m just astounded, and I have no idea why something like this would happen.'

She added: 'We’re just having a really, really hard time here. It’s the worst nightmare any parent could ever have.'

Trusted: It is believed the Krims went to Yoselyn Ortega's home, pictured, in the Dominican Republic in February

Adored: Mrs Krim often wrote about Leo's cute habits, like pretending to cook in his make-believe kitchen

Last post: Mrs Krim regularly writes a blog with pictures of the family and wrote this hours before Leo's death

Mrs Krim, who teaches weekly art lessons to children, kept an online journal entitled 'Life with
the Krim Kids', which she had last updated just three hours before the
murders.

She had written: 'Leo speaks in the most adorable way possible.'

The online
journal paints a tender picture of her life with her husband and their
beloved children, and gives an insight into the horrendous loss that has befallen the
family.

She documents trips to pick apples,
visits to pumpkin patches and playdates. Photographs show the children
playing happily together around the home and on their first days of
school.

'One of the best
parts of my day is after I drop both girls off at school and have 3
precious hours with little Lito all to myself,' she wrote. 'Ok, I’m near
getting cheesy I adore this boy so much!!!'

Close: Scores of pictures on the online blog show the three children playing happily together at the home

Adventures: The family even went to stay with the nanny's family in the Dominican Republic

Adorable: Lulu is pictured with her younger sister Nessie, who was with her mother at the time of the killings

She added how he
loved to play with toy cars and trucks, and would set up his own
'kitchen' in the living room where he would pretend to make bacon.

'Lito, I must say,
is a very clever little boy,' she wrote. 'He is super talkative and
just has a million thoughts running through his brain and can express
himself amazingly well for an almost-2 year old. I'm thinking he could
be a Mini-Kevin.'

The family lives in one of the city's most idyllic neighborhoods, just a
block from Central Park and a few more from the Lincoln Center for the Performing Arts.

It is home to
many affluent families, and seeing children accompanied by nannies is
an everyday part of life there, making the idea of such violence even
more disturbing to residents.

Mrs Friedman added that the Krims are a quiet, nice friendly' family.

Details: New York Police Commissioner Ray Kelly recounted the sequence of events in the harrowing incident at a news conference at NYPD Headquarters in New York on Friday morning

She said: 'They were sweet people. They had two large dogs they used to walk, they were greyhounds I think. The children were full of life.'

All morning a steady stream of passers by stopped off at the apartment block to lay flowers, some of whom were in tears.

Among the tributes was a card on some flowers which read: 'Dear Krim Family. We weep with you at your horrible loss. There are no words that can express our sadness. We pray for you and your beautiful children.

'Every mother and father weeps with you and your family during this dark time'.

Police officers could be seen taking bags of evidence out of the building and at one point removed what appeared to be a long piece of wood which was about 12ft long.

'LIFE WITH THE KRIM KIDS': DOCUMENTING A HAPPY FAMILY

Marina Krim's online journal, Life with the Krim Kids, paints a tender picture of life with her husband and their children - and gives an insight into the horrendous loss that has befallen the
family.

Consisting of mostly photographs, the blog documents trips to pick apples,
visits to pumpkin patches and playdates. Images show the
children playing happily together around the home, on their first
days of school and at ballet recitals

'One of the best
parts of my day is after I drop both girls off at school and have 3
precious hours with little Lito all to myself,' she wrote. 'Ok, I'm near
getting cheesy I adore this boy so much!!!'

'Lito, I must say,
is a very clever little boy. He is super talkative and
just has a million thoughts running through his brain and can express
himself amazingly well for an almost-2 year old. I'm thinking he could
be a Mini-Kevin.'

Hours before his death, she wrote: 'Leo speaks in the most adorable way possible.'

Of her eldest
daughter Lulu, who was also killed on Thursday, she joked: 'Lulu is in
love. His name is Joakim, he's 1/2 British, 1/2 Swedish. He lives in
our apartment building and speaks with a British accent, is a total
hipster and we love his parents. She gets totally giddy around him. Not
sure Lulu knows this but Joakim has 2 other girlfriends as well...'

She later added:
'Lulu has another boyfriend -- When I picked her up from school
yesterday, she told me that Martin (pronounced 'Mar-teen', he's
half-french, half-peruvian) is her boyfriend and her valentine.
Apparently, she kissed him twice.'

Last year, she wrote: 'When I ask Lulu what she wants to be when she grows up, she always says she wants to be a Mama. And she is going to be a really good one.'

In February, she added photos from the family's trip to the Dominican Republic, where they saw the family of their nanny.

'It was wonderful,' she wrote. 'And we met Josie's amazing family! The Dominican Republic is a wonderful country!!'